Schaff, Philip. History of the Christian Church (The Complete Eight Volumes in One). Amazon Kindle Edition, 2014.
Volume 2, Ante-Nicene Christianity A.D. 100-325, “Chapter 5. Christian Worship” (Includes an introduction and sections 59-74).
§64. The Epiphany.
Schaff continues filling in the church calendar with the Feast of Epiphany (Schaff 2014, Loc. 15065). This celebration was begun in the East, but faced resistance even there. Epiphany is the recognition of the appearance of Jesus as Messiah. The Eastern church restricts Epiphany to a celebration of the baptism of Christ. In the West it includes the visit of the Magi and several other events in which Jesus was revealed to people (Schaff 2014, Loc. 15073). Schaff notes that the first traces of a specific Nativity celebration are seen in a homily of Chrysostom from December 25, 385 (Schaff 2014, Loc. 15079).